Lighting system.



B. B. JAGOBSON.

LIGHTING SYSTEM.

. APPLICATION FILED MAY2, 1912.

1,10%,194, U Patented June 30, 1914.

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EDWARD B. JACOBSON,

F PIT'IYSFIELD, IVLASSACHUSETTS, ASSIGNOR. TO. 3' AND. B.

MANUFACTURING COMPANY, OF PIT'ISFIELD, MASSACHUSETTS, A CORPORATION ormassacnusn'rrs LIGHTING SYSTEM.

Specification of Letters Patent.

Patented June 30, 1914.

Application filed May 2, 1912. Serial Np. e94 681.

To all whom it may, concern a citizen of the United States, residing atPittsfield, in the county of Berkshire and;

State of Massachusetts, have invented certain new and usefulImprovements in Lighting' Systems, of which the following is aspecification.

My present invention relates to lighting systems and particularly tolighting systems employed in connection, with motor vehicles.

Such systems are usually operated by means of a magneto generator as thesource of electrical energy, producing an alternating current, andinclude one or more incandescent lamps, which are controlled through themedium of a switch. In previous known forms of like systems; certainmaterial objections are to be noted, namely, the lamps are placed inseries in the same circuit, whereby the use of one lamp involves theoperation of all and the opening of the circuit extinguishes allfurther, the operation of the engine at low speeds fails to operate thelamps; and lastly, the absence of means for controlling and regulating t1e energy from the source of current whereby a substantially constantvoltage at the lamps is effected irrespective of engine speed.

T remedy these objections constit e the essential object of my presentsystem.

The foregoing and other objects I accomplish by means of a lightingsystem for motor vehicles which comprises 'as 'its essential features amagneto generator or other suitable source of "alternating-currentenergy, one or more incandescent lamps, each lamp beingplaced inaseparate circuit or otherwise capable of operation independently ofevery other lamp, an impedance or choke coil or other equivalent meansin circuit with the source of current and adapted to maintain anapproximately constant current in the circuit, and a switch interposedin each lamp-circuit. Y

I will proceed to describe a specific useful form of embodiment of myinvention, in connection with the accompanying drawings, wherein- Figurel is a vertical sectional view -of an impedance coil constructed inaccordance with the objects of my invention; Fig. 2, a top view of thebase of the coil; and Fig. 3, a diagrammatic planview of a lightingsystem constructed and arranged in accordance with my invention.

The impedance coil herein shown comprises a base 1, core magnets 2, 2,mounted on the base 1 and arranged in parallel, coils or windings 3, 3,carried by the cores '2, 2, casings 4', 4, mounted on the base 1 ands'ur-' rounding the coils 3, 3, and suitable terminal facilities'5, 5,providing a common feed connection and separate ground connections forthe'coils.

The base 1 is shown as a plate, preferably circular in form andconstructed of magnetic metal, having suitable marginal lugs 7, 7, 7,for connection witha support, and provided on its upper'face with spacedrecesses 8, 8, into which the lower ends of thecasings 4, 4, are fitted.Seated in recesses 9, 9., provided in the base centrally of the'recesses8,, 8-, are shown upright metallic cores or magnets2, 2, preferablyformed of a bundle of soft-iron wires, extending upward into the casings4, 4. Mounted on the cores 2, 2,

and preferably disposed about the upper ends thereof are shownseparatewindings 3, 3, having their lower leads 10, 10, extending downthrough suitable openings 11, 11, extending laterally'from andcommunicating with a recess12 provided in the under side of the base,-the leads 1Q, 10, being connected to a common terminal 6 provided insaid recess 12 and extending upward t rough a suitable aperture in thebase to form a bind in -post on the upper face of the base from which itis suitably insulated,

The casings 4, 4, are shown as upright cylinders which are open at theirlower ends and-are closed at their upper ends by suitable insulationdisks or plates 13, 13, disposed freely over the cores 2, 2. Mounted onthe disks 13, 13, are shown the terminals 5, 5, in the form ofbinding-posts, to which the leads 14, 14, at the upper ends of thewindings 3, 3, are respectively electrically connected, I

While I have preferred to construct the base 1 of magnetic metal, suchas soft iron, to -'provide an air-gap between the upper ends of thecores 2, 2, and .to arrange the windings in such manner that adjacentends of the cores 2, 2, are of like polarity, these features I do notclaim as essential to the operation of the system. Modifications thereofmay be made by the provision of a closedmagnetic circuit or endlesscore, by variations in the number of turns in the windings, by arrangingthe windings so that the adjacent ends of the cores have like poles, orotherwise, but I have found by experimentation that the constructionherein shown is productive ofgreater efiiciency.

In the arrangement of the system, the

lamps 17 are each placed in a separate cire' cuit' with the source ofcurrent 15, having separate ground connections and a common feedconnection at the switch 16. Between the switch 16 and the lamps 17, Iinterpose in the separate lamp circuits 18, 19, an impedance coil commonto both circuits, and which: preferably comprises separate adjacentcores 2, 2, on which respective windings 3, 3, are laced for separateconnection with the circuits 18, 19, the. cores being magneticallyclosed by a yoke or base 1 at one end and open at theopposite end,thereby providing an air-gap- Assuming the engine to be running and theswitch 16 to be closed in both circuits, the currentgenerated at 15flows through the windings 3, 3, and the lamps 17,1 7, setting up areactance in the impedance coil which regulates the current andmaintains an approximately constant voltage at the lamps. The currentgenerated at the source of current usually has a voltage largely inexcess of that required for the operation of the lamps, and, unlessreduced, would burn them out. Moreover, this voltage is variable,increasing with the speed of the engine. .An essential feature,therefore, of the present system is the introduction into the circuit ofan impedance coil producing a reactance in the circuit and which variesapproximately proportionately to the frequency of current alternations,

maintaining'a substantially constant current in the circuit, In previousknown systems, the absence of similar controlling means causes the lampsto largely vary in illuminative strength, rising or fallin with thevoltage in the circuit, and fins. y to flash out as the speed of theengine increases to a maximum.

By means of'the several lamp circuits and a switch for controlling eachcircuit independently of the other, one ofthe circuits may be opened orclosed during the operation of the other circuit and without afiectthenormal operation of the impedance 0011 in the circuit in use.

It may be further observed that I do not a limit myself in the presentsystem to the use of any particular number oflamps at one time, as thenumber may be increased indefinitely within thelimits of the capacity inthe source of current, providin however, that a separate circuit incluing an additional magnetic core and se arate winding thereon be addedfor eac additional employed.

lamp I T e present system is designed to obviate the necessity of usinga separate magneto generator exclusively for lighting pur oses, as it isadapted to include the source 0 electrical energy for ignition purposesas a source ofenergy for the operation of the lamps, on vehiclesemploying a magneto In testimony whereof'I hereto aflix myri d signaturein presence of two witnesses.

EDWARD B. JACOBSON.

Witnesses:

FLOYD A. KNIGHT, J No; WHI'I'I'LESEY.

